Machine for treating wood pulp and the like



MACHINE FOR TREATING WOOD PULP AND THE LIKE Filed April 16, 1958 INVENTOR. JAMES 7.' COG/ ILL ATTORNEY KN United States Patent Q 3,028,634 MACHINE FOR TREATING WOOD PULP AND THE LIKE James T. Coghiil, Pittsford, N.Y., assignor to Cnrlator Corporation, East Rochester, N.Y., a corporation of Delaware Filed Apr. 16, 1958, Ser. No. 728,893 2 Claims. (Cl. 19--66) The present invention relates to machines for processing fibrous material and particularly to machines for processing wood pulp for making paper. In a more specific aspect, the invention relates to machines of the type disclosed in my copending application Serial No. 697,166, filed November 18, 1957, for mechanically processing wood pulp according to the method disclosed in the Hill and Edwards Patent No. 2,516,384, granted July 25, 1950.

In the process of Patent No. 2,516,384, the pulp, which is to be treated, is rolled traversingly in different directions in tractive contact with and under pressure between two opposed working surfaces that are knurled to provide the required traction. nodulated, but if not, it will be formed, as it rolls between and over the working surfaces under compression, into nodules in which the fibers of the pulp are intertwined and curled on one another. As the modulated pulp is rolled traversingly under compression between and over the working surfaces, the nodules of the pulp will be formed into rotatable units, and these units will be caused to travel rollwise under compression, thereby causing continuous reorientation of the fibers relative to the direction of applied pressure. Thus, the pulp fibers or fiber bundles will be bent, and twisted, and subjected to increased contortion as the units of nodules roll traversingly over the working surfaces. This causes separation or liberation of the fibers which may be bonded together, without multilating the fiber structure or forming fiber debris. Thus, the method of Patent No. 2,516,384 provides an effective means of eliminating the small, but undesirable, shive content of regular commercial grades of pulp, such as sulphite, kraft, and soda pulp. Moreover, it supplies a much'needed step in the production of so-called high-yield or semi-chemical pulps, all of which require reduction of fiber bundles while retaining high freeness in order to facilitate further processing and form a clean sheet of paper. The method of Patent No. 2,516,384 unbonds or liberates the individual fibers to an essentially complete degree with a very low expenditure of power and without sacrifice of freeness.

In the machines, which have been built previously for practicing the invention of Patent No. 2,516,384 one of the working surfaces has been stationary; and the rolling of the pulp travers'ingly between the working surfaces has been achieved by imparting a gyratory or orbital motion to the other working surface. In these prior machines, furthermore, control of the speed of the rolling feed of the stock across the working surfaces, has depended largely upon the angles of the teeth or protrusions on the opposed knurled working surfaces. With prior types of machines, at least four different types of working surfaces have had to be provided, these types differing from one another in the direction of inclination of their teeth or protuberances. The type of working plate employed has depended on the desired rate of feed of the pulp and the kind of pulp.

The directionalism of the working surfaces, that is, the direction of inclination of the protuberances, changes, however, with the age of the working plates, that is, with wear. Heretofore, there has been no satisfactory way of compensating for wear. Heretofore, all that could be The pulp may previously be floating plate, rotates because the pulp between the working surfaces acts to transmit the motion of the driving plate to the floating plate. Both working surfaces, therefore, rotate in the same direction. In this machine the axes of the two working surfaces are offset from one another so as to achieve a relative gyratory or orbital motion of the working surfaces, thereby to effect the curling roll of the pulp between the working surfaces; and control of the rotational speed of the floating plate is attained by tilting one plate relative to the other. This machine, however, lacked means for controlling the rate of traverse of the-pulp between and across the working surfaces. I

One object of the present invention is to provide a machine of the character described in which the rate of rolling traverse of the pulp between and over the working surfaces can readily be controlled.

Another, related object of the invention is to provide a machine of the character described in which the rate of speed of traverse of the pulp between and over the working surfaces can be varied at will by a simple adjustment of the machine and without changing the working surfaces. Hence, it is easy to compensate for wear of the working plates, or for different stocks.

Another object of the invention is to provide an improved machine of the character described in my pending patent application above-mentioned, which will permit use of the relative rotational speed of the plates in that machine, to affect variable traverse of the stock.

Other objects of the invention will be apparent hereinafter from the specification and from the recital of the appended claims when read in conjunction with the accompanying drawing.

' In the drawing:

FIG. 1 is a diagrammatic view showing somewhat exaggeratedly how the working surfaces of a machine made according to my copending application above mentioned may be tilted relative to one another to achieve control of the speed of the floating plate relative to the driven plate;

FIG. 2 is a diagrammatic view looking at right angles to the view of FIG. 1 and further indicating the relation of the working surfaces when both working surfaces are provided with protuberances which are inclined outwardly, that is, toward the peripheries of the working surfaces according to the principles of the present invention;

FIG. 3 is a fragmentary view looking in the same direction as FIG. 2, but on a much larger scale, and showing further details of the preferred structure of the working surfaces;

FIG. 4 is a fragmentary section also on an enlarged scale, illustrating further the outwardly inclined direction of the protuberances of both working surfaces; and

FIG. 5 is a diagrammatic View further illustrating how each working surface is constructed.

In a machine built according to the present invention, just as in the machine of my copending application above mentioned, one working surface drives the other through the pulp disposed between the two working surfaces, one plate being pressed toward the other; the axis of one working surface is offset from the axis of the other Working surface; and the floating surface is tiltable relative to the driving surface in order to control the relative speeds of rotation of the two plates. In a machine constructed according to the present invention, there is an additional feature incorporated, the working surfaces are both made with directional working plates, and these plates both have their protuberances or teeth inclined outwardly toward the peripheries of the espective working surfaces. Preferably, also, the protuberances on the two working surfaces are so directed that the protuberances on one surface are inclined to or cross the protuberances on the other surface. Preferably, also, the two working surfaces are identical. This last feature can be achieved by making the protuberances on both surfaces extend non-radially of the axes of the two working surfaces, and along center lines equally offset from those axes.

Reference may be had to my cop ending application above mentioned for details of structure of the machine. The description herein will be confined to such principles as are necessary to an understanding of the present invention and to details of the structure of the working surfaces which in combination with the tilt adjustment of the machine of my copending application make possible complete control of the rate of feed or traverse of the pulp between and over the working surfaces.

Referring now to the drawing by numerals of reference, it denotes the driving plate which is driven positively at a constant speed by the motor of the machine. This plate carries one set of working surfaces. ii. is the floating plate. This plate carries the opposed set of working surfaces, and rotates because the pulp P between the working surfaces acts to transmit the motion of the driving plate 1% to tlr floating plate 11.

In the machine of my copending application mentioned, the floating plate 11 is adjustable relative to the driving plate it. so that the axis 23 of the floating plate is ortse from the axis 22 of the driving plate, so as to achieve the relative gyratory or orbital motion required to effect the curling roll of the pup between the working surfaces. In the machine of my copending application, also, the floating plate 11 is tiltable relative to the driving plate so that, in use, the axis 23 of the floating plate 11 is inclined to the axis 22 of the driving plate 16. Both these features of my prior application are made use of in the present invention. If the floating plate 11 is tilted as indicated in FIG. 1, so that the pressure is greater at point A than at point B, the plate 11 will run faster than the driving plate I'll; and if the floating plate 11 is tilted so that the pressure is greater at point B than at point A, floating plate 11 will run slower than driving plate 10. Points A and B are on a line passing through the axes of both plates. In the instance illustrated in the drawings, the axis 22 of the driving plate is offset in a vertical plane from the axis 23 of the floating plate, and points A and B are on the vertical center line of the axes.

In the machine of the present invention, each working surface comprises a plurality of concentrically arranged groups of surface plates, such as denoted diagrammatically at 12, 13 and 14 in FIG. 5. Each of these surface plates has a plurality of pyramidal projections or protuberances 15 that lean outwardly, as shown in P16. 4, toward the discharge Zone for the pulp around the peripheries of the floating and driving plates 1d and 11. These protuberances may be made by milling each surface plate with formed tools along two lines which are inclined to one another and which are both oflset from the axes of the respective working surfaces, thereby to produce grooves 16 and 17 in the surface plates which bound the teeth or protuberances 15.

The individual surface plates may be all made alike but preferably are constructed as indicated diagrammatically in PEG. 5. Thus, the surface plates 12 of the radially innermost group have their teeth formed so that the centerlines of these teeth extend in the directions denoted by arrows 18 at an angle of say 45 to lines radial of the axis of the respective driving or floating plate It} or 11. Likewise the surnzce plates of the intermediate group 13 have the centerlines of their teeth inclined in the direction 18' at an angle of say 45 to a radial line 25; and similarly the surface plates of the outermost group 14 have the centerlines of their teeth inclined in the direction 18 at an angle of say 45 to a radial line 25. The arrows 18, 18, 18" denote the outward lean or inclination of the teeth. The centerlines of the teeth are all offset from the axis of plate 16 or 11, respectively, and tangent to a circle circumscribed about the axis of the respective working plate.

The two working plates are preferably identical. Therefore, when they are opposed to one another as shown in FIGS. 1, 2, 3 and 4 the centerlines of the opposing teeth or protuberances 15 of the two plates cross one another as denoted by the arrows 2d and 21 in FIG. 2, the arrow 2-1) denoting the direction of the protuberances or teeth or the working plate 10, and the arrow 21 denoting the protuberances or teeth of the working plate 11.

If now the floating working surface 11 is tilted, as indicated in FIG. 1, so that the pressure is greater at point A than at point B, the plate 11 will run faster than the driving plate It and the opposing directionalism of the protuberances on the two working surfaces will tend to propel the pulp outwardly; and there will be a greater tendency of the pulp to traverse the working surfaces radially toward their peripheries. In this case, the directionalism of the working surfaces will accelerate the movement of the pulp. If, on the other hand, the floating plate 11 is tilted so that the pressure is greater at point B than at point A, floating plate 11 will run slower than the drive plate 1i and due to the crossed action of the two p ates, there will be a tendency for the protuberances 15 on the working surfaces 10 and 11 to resist outward radial travel of the pulp. By varying the tilt of the floating plate relative to the driving plate, then, change in speed of the plates can be achieved which, with the opposed directionalism of the two working surfaces, gives complete control of the rate of feed of the pulp betwecn the plates. In practice, the working surfaces are adjusted to one another so that their difference in speed wil be in the order of one to five rpm. for five hundred rpm. of the driving surface 10.

As the plates revolve, the stock is rolled outwardly toward the edges of the plates being urged outwardly by centrifugal force and the directional construction of the plates but with tilt adjustment and the crossed directionalism of the plates the rate of outward movement of the stock can be controlled; and this rate of outward movement can be held to uniformity within a satisfactory degree. With the plates designed as described above, it is possible to hold or to advance the material at will, thereby to insure curling of the pulp, and curling to the proper degree.

While the invention has been described in connection with a specific embodiment thereof, it will be understood that it is capable of further modification, and this application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice in the art to which the invention pertains and as may be applied to the essential features hereinbefore set forth, and as fall within the scope of the invention or the limits of the appended claims.

Having thus described my invention, what I claim is:

1. In a machine of the character described for treating stock material, and which has two rotating plates whose axes are offset from one another, and having means for rotating one plate positively, the other plate being adapted to be driven from said one plate solely by the material being treated between the plates whereby the two plates rotate in the same direction, and having means for forcing said other plate against said material by regulatable pressure, and having means for mounting said other plate so it is free to float axially toward and away from said first plate responsive to the balance of forces between said material and said pressure, and having means for supporting one of said plates for tiltable adjustment relative to the other plate thereby to control the relative rotational speeds of the two plates, and wherein the working surfaces on the two plates are identical and opposed to one another, and wherein each working surface comprises a plurality of tiny, spaced, pyramidal protuberances projecting from the working surface into the Working space between the plates, and wherein said protuberances provide traction for the material without obstructing rolling traverse of the material on and over the working surfaces, the improvements comprising having all of the protuberances on the two surfaces inclined outwardly toward the discharge zone around the peripheries of the two plates, and having the protuberances on each working surface extending in directions inclined to lines radial to the axis of the respective working plates.

2. In a machine for treating papermaking pulp having two opposed working plates which are supported for rotation about axes that are offset, respectively, from one another, each plate having a working surface thereon, the two plates being disposed so that their working surfaces form between them a thin working space, each Working surface having a plurality of tiny, spaced pyramidal protuberances thereon projecting into the working space to provide traction for pulp without obstructing rolling traverse of units of pulp on and over the working surfaces, there being a plurality of such spaced protuberances on each working surface along any line radial of the axis of rotation of the working surface, means for positively driving one of said plates, means for continuously urging one plate toward the other so that the other plate is driven from the positively-driven plate solely through the pulp engaged between the plates, and one of said plates being mounted for tiltable adjustment relative to the other plate thereby to control the relative speeds of rotation of the two plates, the improvement comprising each individual protuberance on each of the two working surfaces being inclined outwardly toward a discharge zone around the peripheries of the two plates, and the protuberances on one surface being disposed so that the directions in which the protuberances of that surface extend are inclined to the directions in which the protuberances on the other surface extend.

References Cited in the file of this patent UNITED STATES PATENTS 1,058,114 Symons Apr. 8, 1913 1,719,784 Ross July 2, 1929 2,589,307 Symons Mar. 18, 1952 2,646,728 Coghill et al. July 28, 1953 2,674,928 Coghill Apr. 13, 1954 2,884,036 Symons Apr. 28, 1959 FOREIGN PATENTS 215,555 Great Britain May 15, 1924 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No, 3 O28,634 April 10 1962 James To Coghill It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Ir 1 the grant line 3, and in the heading to the printed specification, lines 5 and 6, for "a corporation of Delaware" each occurrence, read a corporation of New York Signed and sealed this 4th day of September 1962.,

SEAL) Kttest:

ERNEST w. SWIDER DAVID L- A D mesting Officer Commissioner of Patents 

